Self-locking control device



J. M. CURTIN 2,855,800-

SELF-LOCKING CONTROL DEVICE Oct. 14, 1958 2 Sheets-Sheet 1 Filed Nov. 14, 1955 By Ms 47r dR/VEL/8 115 19275, E/EZH, Fsree ffiveels.

Oct. 14, 1958 u. CURTIN SELF-LOCKING CONTROL DEVICE 2 sheets-sheet 2 7 Filed NOV. 14, 1955 SELF-LOEIKING CONTROL DEVICE John M. Curtin, Studio City, Calif., assignor to Hansen- Lynn (30., Inc., Burbank, Califl, a corporation of California Application November 14, 1955, Serial No. 546,616

16 Claims. (Cl. 74-531) The present invention relates in general to control devices and, more particularly, to a self-locking, irreversible control device which may readily be unlocked by the operator to perform some operation on an apparatus controlled by the device, but which cannot be unlocked by forces applied thereto by the controlled apparatus.

In general, the invention contemplates a self-locking, irreversible control device comprising a track member and a locking unit one of which is movable relative to the other in a direction along the track member, the locking unit preferably being movable relative to the track member so that the latter acts as a stationary anchor member engageable by the locking unit to lock it many desired position on the track member. The locking unit of the device includes a locking means which is engageable with the anchor or track member and which preferably utilizes locking elements in the form of rollers,

such rollers preferably being cylindrical, although rollers of other shapes, such as spherical rollers or. balls, may be employed. The locking means provides a surface which cooperates with a surface of the track member to provide therebetween a space having an enlarged central portion and convergent end portions, and provides two roller locking elements biased 'into the convergent end portions of such space. The control device of the invention also provides means for selectively moving the roller locking elements into the central portion of the space in which they are disposed to permit movement of the locking unit relative to the track member in one di-. rection or the other.

A primary object of the invention is to provide a locking unit including a supporting member on which the locking means is loosely mounted so that it may float relative to the supporting member. With this construction, the locking action is uniform even if the track member and the locking unit are not positioned relative to each other completely accurately due to manufacturing errors, warping of parts, or the like. Consequently, the present invention, by providing the locking .nnit with a floating, self-aligning locking means, permits much larger manufacturing tolerances than would otherwise be the case, which is an important feature.

Another object is to provide a floating locking means whichincludes a floating member loosely mounted on the supporting member and cooperating with the rollers and the track member to lock the locking unit relative to the track member, such floating member being disposed in a slightly enlarged, complementary recess in the supporting member .toprovide the desired floating action.

The aforementioned convergent-ended space provided by the locking means is defined by a surface ofthe floatrnember and a surface of the track member, the roller lockingelements being disposed between such surfaces of the track member and the floating member. In this connection, an important object of the invention is tomakethefloating member a heavy, rigid, C-shaped limited States Patent M member having two arms which span the track member 2,855,800 Patented Oct. 14,

and receive it therebetween, the aforementioned surface of the floating member being provided by one of the arms thereof.

Another important object of the invention is to provide the other arm of the C-shaped floating member with a shoe which slidably engages a surface of the track member on the opposite side of the track member from the surface thereof which is engaged by the roller locking elements. Thus, the reaction of the roller locking loads resulting from wedging the rollers into the convergent ends of the space in which they are disposed is taken by the heavy, G-shaped member, and these rollers locking loads are not applied to the track member, or to any other part of the structure. This provides a control device of maximum rigidity without necessitating any extremely rigid parts, except for the C-shaped member. For example, the track member may be relatively thin since the roller locking loads applied to one side thereof are opposed by the shoe engaging the opposite side thereof.

Another object of the invention is to adjustably mount the aforementioned shoe on the C-shaped member so as to properly align it with the track member, thereby permitting larger manufacturing tolerances.

An important feature of the invention is that, with the foregoing construction, large roller looking or. wedging loads may be utilized for a positive locking action while still utilizing the open-sided C-shaped memberdescribed. An advantage of this is that, by utilizing the C-shaped member in a control device wherein the track .member is arcuate, the track member may simply be an axially extending flange of an arcuate angle member having a radial flange which is secured to a suitable supporting structure. With this construction, there is free access for the rollers to the axially extending flange of the angle member throughout a full 360 degrees so that full 360- degree rotation of the locking unit is possible without any interference from any mounting means.

The foregoing objects, advantages, features, and results of the present invention, together with various other objects, advantages, features and results thereof which will be evident to those skilled in the art in the light of this disclosure, may be attained with the exemplary embodiments of the invention which are illustrated in the accompanying drawings which are described in detail hereinafter. Referring to the drawings:

Fig. l is an elevational view of a self-locking, irl'CVfiIsible control device of the invention;

Fig. 2 is an enlarged sectional View takenalong the irregular arrowed line 2-2 of Fig. 1;

Pig. 3 is a fragmentary sectional view the arrowed line 33 of Fig. 2;

Figs. 4, 5 and 6 are isometric views showing three different components of the locking device of the invention;

Fig. 7 is an elevational view of another embodiment of the invention with parts broken away; and

Fig. 8 is a sectional view taken along the irregulararrowed line 8-8 of Fig. 7 of the drawings. I

Referring particularly to Figs. 1 to 3 of the drawings, illustrated therein is a self-locking, irreversible control device 10 of the invention which includes a suitable supporting structure 12 for various components of the device. The supporting structure 12 may have any desired configuration, the one illustrated being exemplary only.

Mounted on the supporting structure 12 for pivotal movement about a common axis are a driving lever 14 and a driven lever 16, the driving lever being mounted on bearings 18 on a shaft 20 carried by the supporting structure 12, and the driven lever 16 being similarly mounted on bearings 22 on the same shaft. The driving lever 14 includes a handle 24 which, in the particular construction illustrated, is mounted on a pivot 26 pert n s j pendicular to the pivot axis of the driving and driven levers 14 and 16 for a specific application of the invention which need not be described herein. For the purpose of this disclosure, the handle 24 may be re garded as an integral part of the driving lever. The driven lever 16 is provided with a yoke 28 to which is pivotally connected a link 30 leading to any suitable apparatus or mechanism to be controlled by the device 10. As will hereinafter be explained in detail, the link 30 may be moved readily in either direction by move ment of the driving lever 14. However, the device is irreversible so that any forces applied to the link 30 by the controlled apparatus will not displace the driving and driven levers 14 and 16.

The control device 10 includes a track member 32 which, in the particular embodiment under consideration is arcuate and which, in the particular construction illustrated, is stationary so that it serves as an anchor member for the driven lever 16, as will be described. The track member 32 is shown as formed by an axially extending flange of an arcuate angle member 34 the center of curvature of which is the pivot axis of the driving and driven levers 14 and 16. The track member 32 defines at least a portion of a hollow cylinder in the particular construction illustrated. The track member 32 is secured to the supporting structure 12 by riveting, or otherwise fastening, a radially extending flange 36 of the angle member 34 to the supporting structure 12. It will be noted that track 32 provides outer and inner track surfaces 38 and 40, the surfaces 38 and 40 sometimes being referred to herein as first and second surfaces, respectively.

The driven lever 16 comprises a locking unit which is movable along the track member 32 and which is engageable with the track member to lock the driven lever in any desired position along the track member, this locking unit including a floating locking means 42 mounted on the driven lever so that the driven lever serves as a supporting member therefor. As best shown in Fig. 2 of the drawings, the driven lever 16 is provided therein with a substantially hemicylindrical recess 44 into which the track member 32 extends. The floating locking means 42 includes a C-shaped member 46, best shown in Fig. 4, having arms 48 and 50 which span the track member 32 and receive it therebetween, the C- shaped member 46 having a substantially hemicylindrical portion 52 which is disposed in the recess 44 in the driven lever 16 and which is smaller than such recess so that the C-shaped member 46 floats radially relative to the driven lever. The difference between the diameters of the hemicylindrical portion 52 of the C-shaped member 46 and the recess 44 may be of the order of magnitude of 0.015 inch to 0.040 inch to provide the desired floating action. Endwise movement of the C-shaped member 46 is limited by end flanges 54 thereon which receive the .driven lever 16 therebetween. Movement of the hemicylindrical portion 52 of the C-shaped member 46 out of the recess 44 is prevented by a plate 56 and a washer 58 which are riveted, or otherwise secured, to the driven lever 16 and which extend over the open side of the recess 44, as best shown in Fig. 2 of the draw ings. As will become apparent, this floating mounting of the C-shaped member 46 on the driven lever 16 compensates for manufacturing errors, such as inaccuracies in locating the center of curvature of the track member 32 relative to the pivot axis of the driving and driven llelllers 14 and 16, warping of the track member, and the As best shown in Fig. 3 of the drawings, the inner arm 50 of the C-shaped member 46 provides a surface 60, sometimes referred to herein as a third surface, which faces and is spaced radially inwardly from the inner surface 40 of the track member 32. The surface 40 is concave relative to the surface 60 so as to provide therebetween a space 62 having an enlarged central portion and convergent end portions. Disposed in the space 62 are two rollers 64 which are biased into the convergent end portions of the space by a compression spring 66 located therebetween, the rollers and the spring being retained in the space 62 by the aforementioned plate 56. As will be discussed in more detail hereinafter, the rollers 64 tend to Wedge in the convergent end portions of the space 62 between the surfaces 40 and 60 to prevent movement of the driven lever 16 in either direction un der the influence of forces applied to the link 36 by the controlled apparatus.

The outer arm 48 of the C-shaped member 46 carries a shoe 68 which slidably engages the outer surface 38 of the track member 32. The shoe 68 is mounted on the C-shaped member 46 by means of adjusting screws 70 extending through the end flanges 54 of the C- shaped member 46 into engagement with the shoe. With this construction, the shoe 68 may be adjusted relative to the C-shaped member 46 for proper sliding engagement with the outer surface 38 of the track member, which is an important feature.

In order to permit movement of the driven lever .16 in response to the application of an operating force to the driving lever 14, the latter has bolted, or otherwise secured, thereto a yoke 72 provided with arms 74 engageable with the respective rollers 64, as best shown in Fig. 3 of the drawings, and spaced apart a distance slightly greater than the length of the C-shaped member 46 to provide a lost-motion connection between the driving lever 14- and the driven lever 16. This 10stmotion connection permits the driving lever 14 to be pivoted relative to the driven lever 16 in either direction a distance sufficent for one of the arms 74 of the yoke 72 to engage the corresponding roller 64 and move it out of wedging relation with the surface 40 of the track member 32 and the surface 60 of the C-shaped member 46. For example, if the driving lever 14 is moved in the clockwise direction, as viewed in Fig. 3 of the drawings, the left arm 74 of the yoke 72 engages the left roller 64 to move it out of wedging relation with the surfaces 40 and 60. Thereafter, the left arm 74 engages the left end of the C-shaped member 46 to permit clockwise movement of the driven lever 16 in response to continued clockwise movement of the driving lever 14. Of course, the reverse occurs in response to counterclockwise movement of the driving lever 14. Thus, movement of the driven lever 16 can occur only in response to movement of the driving lever 14, the driven lever being locked against any forces applied thereto by the controlled apparatus through the link 30.

As will be apparent, the C-shaped member 46, which has a relatively heavy and rigid construction, takes all of the radial wedging or locking loads produced by wedging of the rollers 64 in the convergent ends of the space 62. The inner arm 50 of the C-shaped member 46 takes these wedging loads directly since the surface 60 is formed thereon, and the outer arm 48 takes the locking leads through the track member 32 and the shoe 68. Thus, the outer arm 48 of the C-shaped member 46 backs up the track member 32 through the shoe 68 so that the track member may be a relatively light one. Also, since the C-shaped member 46 takes all of the locking loads, there is no tendency to distort the driven lever 16, and thus possibly strain the pivotal connection between the driving and driven levers 14 and 16 and the supporting structure 12. Consequently the use of this heavy C-frame construction permits high wedging forces without requiring the use of excessively rigid parts throughout the rest of the device.

The floating action of the C-shaped member 46 is important since it provides a uniform locking action despite manufacturing errors, such as assembling the track member 32 eccentrically with respect to the pivot axis of the driving and driven levers 14 and 16, warping of the supporting structure 12, the driven lever 16, or the track j member 32, or warping of other parts of the device, and the like. Also, the adjusting screws 70 compensate for any manufacturing errors in the (J-shaped member 46 itself, or in other parts of the device, it being possible to render the shoe 68 concentric with respect to the pivot axis of the levers 14 and 16 despite manufacturing errors. Thus, the construction described permits quite wide manufacturing tolerances, which is important.

The =C-shaped member 46 is important in another respect in that the open-sided construction provided thereby permits the track member 32 to be a simple flange which may be mounted on the supporting structure 12 at one side thereof only. Consequently, it is possible with the -C-shaped member 46 to extend the track member 32 throughout a full 360 degrees if full 360-degree rotation of the driving and driven levers 14 and 16 is desired, it

being understood that some changes would be necessary in the supporting structure 12 to accommodate full 360- degree rotation of the driving and driven levers.

Referring now to Figs. 7 and 8 of the drawings, illustrated therein is a control device 80 of the invention which embodies certain of the features'of the control device 10, the principal one being the use of a shoe en- I gageable with a track member to back up the track member, as will be described in more detail hereinafter. The control device 80 includes, generally, a locking unit 82 and a track member 84 which are relatively movable, the locking unit preferably being movable relative to the track member. The control device 80 is not adapted to drive any controlled apparatus, but merely locks and releases a controlled apparatus. For example, the control device 80 may be used to lock and release a seat, not shown, which is movable in a direction parallel to the track member 84, the latter being straight in the particular construction illustrated. In such an environment, the locking unit 82 may be bolted, or otherwise secured, to a bracket 86 attached to and movable with the seat, and the track member 84 may be stationarily mounted in any suitable manner, not shown. 7

The locking unit 82 is shown as including two plates 88 which are secured together by bolts 90 and 92 extending through spacers 94 and 96, respectively, to maintain the plates in spaced-apart relation, the bolts 90 also serving to secure the locking unit 82 to the bracket 86. The track member 84 extends through the opening provided by the plates 88 and the spacers 94'and 96. The lower spacer 94 carries a shoe 98 which is engageable with a surface 100 of the track member 84, this surface sometimes being referred to herein as a first surface. As will become apparent, the shoe 98 backs up the track member 84 so that the latter does not have to take any locking loads, the shoe 98 being mounted on the spacer 94 by means of adjusting screws 102 for rendering the shoe perfectly parallel to the surface 100 of the track member. The opposite surface, 104, of the track member 84 cooperates with a concave surface 106 of the spacer 96 to provide a space 108 having an enlarged central portion and convergent ends or end portions, the surfaces 104 and 106 sometimes being referred to herein as second and third surfaces. Disposed in the space 108 are rollers 110 which are biased toward the convergent end portions of the space by a compression spring 112, thereby wedging the rollers between the surfaces 104 and 106 to lock the unit 82 relative to the track member 84. In order to unlock the unit 82, the device 80 is provided with a handle 114 connected to the plates 88 by a pivot 116 and provided with a yoke 118 having arms 120 respectively engageable with the rollers 110.

As will be apparent, by pivoting the handle 114 in the clockwise direction, the right hand roller 110, Fig. 7, is unwedged to permit movement of the locking unit 82 toward the left, or in a direction opposite to the direction of the unlocking force. The reverse occurs, of course, in response to counterclockwise movement of the handle. Since the unlocking force applied to the handle 114 is in a direction opposite to the direction of movement of the locking unit 82 permitted by such unlocking force, it will be understood that the unlocking force applied to the handle cannot be used to drive the locking unit 82 along the track member 84. Thus, the control device is limited to installations wherein the driving force for moving the locking unit 82 along the track member 84 is supplied in some other way. For example, when the control device 80 is used to lock a movable seat, the driving force may be provided either by the occupant of the seat, or by springs connected to the seat.

If it is desired to employ the control device 80 in an installation wherein it is desired to use the unlocking force applied to the handle 114 as a driving force for moving the locking unit 82 along the track member 84, it would be necessary to provide some means for causing the unlocking force applied to the handle 114 to act in the desired direction of movement of the locking unit 82 along the track member. This may be accomplished, for example, by interposing suitable gearing, not shown, between the handle 114 and its yoke 118 to reverse the direction of the unlocking, force required to unwedge a particular one of the rollers 110.

It will be noted that the provision of the shoe 98 in the control device 80 has the same advantage as the shoe 68 in the control device 10, viz., it backs up the track member 84 to take the locking loads resulting from wedging of the rollers in the convergent end portions of the space 108. Thus, the track member 84 may be a relatively light member supported at its ends only, for example.

Although I have disclosed specific exemplary embodiments of my invention herein, it will be understood that various changes, modifications and substitutions may be incorporated in such embodiments without departing from the spirit of the invention as defined by the claims hereinafter appearing.

I claim as my invention:

1. In a self-locking control device of the character described, the combination of a track member and a locking unit one of which is movable relative to the other in a direction along the track member, said track member providing first and second surfaces on opposite sides thereof and said locking unit providing a third surface facing and spaced from said second surface, one of said second and third surfaces being concave relative to the other so as to provide therebetween a space having an enlarged central portion and convergent end portions, said locking unit including: two rollers in said space; means for biasing said rollers into said end portions of said space; means for selectively moving said rollers into said central portion of said space; and a shoe in slidable engagement with said first surface of said track member.

2. A self-locking control device as defined in claim 1 wherein said track member is arcuate.

3. A self-locking control deviceaccording to claim 1 wherein said track member is straight.

4. A self-locking control device as defined in claim 1 including means for adjusting said shoe to render same parallel to said first surface of said track member.

5. A self-locking control device according to claim 1 wherein said locking unit includes a C-shaped member spanning said trackmember, said C-shaped member having two arms of which provides said third surface and the other of which carries said shoe.

6. A self-locking control device according to claim 5 wherein said locking unit includes a supporting member for said C-shaped member, the latter being loosely mounted on said supporting member.

7. In a self-locking control device of the character described, the combination of a track member and a locking unit one of which is movable relative to the other, said track member providing first and second surfaces on opposite sides thereof, and said locking unit including: a supporting member; a C-shaped member spanning said track member and loosely mounted on said supporting member so as to float relative thereto, said C-shaped member having two arms one of which provides a third surface facing and spaced from said second surface of said track member, one of said second and third surfaces being concave relative to the other so as to provide therebetween a space having an enlarged central portion and convergent end portions; two rollers in said space; means for biasing said roller into said end portions of said space; and means for selectively moving said rollers into said central portion of said space.

8. A self-locking control device as defined in claim 7 including a shoe carried by the other of said arms of said C-shaped member and in slidable engagement with said first surface of said track member.

9. In a self-locking control device of the character described, the combination of: supporting structure; an arcuate track member carried by said supporting structure, said track member defining at least a portion of a hollow cylinder and having inner and outer surfaces; a driven lever pivotally mounted on said supporting structure for movement about the axis of said track member; a C-shaped member carried by said driven lever and having two arms spanning said track member, one of said arms providing a surface which faces and is spaced from said inner surface of said track member and which cooperates therewith to provide therebetween a space having an enlarged central portion and convergent end portions; two rollers in said space; means for biasing said rollers into said end portions of said space; a driving lever pivotally mounted on said supporting structure for movement about the axis of said track member; and means on said driving member for selectively moving said rollers into said central portion of said space.

10. In a self-locking control device of the character described, the combination of: supporting structure; an arcuate track member carried by said supporting structure, said track member defining at least a portion of a hollow cylinder and having inner and outer surfaces; a driven lever pivotally mounted on said supporting structure for movement about the axis of said track member; a C-shaped member carried by said driven lever and having two arms spanning said track member, one of said arms providing a surface which faces and is spaced from said inner surface of said track member and which cooperates therewith to provide therebetween a space having an enlarged central portion and convergent end portions; two rollers in said space; means for biasing said rollers into said end portions of said space; a driving lever pivotally mounted on said supporting structure for movement about the axis of said track member; means on said driving lever for selectively moving said rollers into said central portion of said space; and a shoecarried by the other of said arms ofsaid C-shaped member and slidably engaging said outer surface of said track member.

ll. A device according to claim 10 including means for adjusting said shoe relative to said C-shaped member.

12. A self-locking control device as defined in claim 10 wherein said C-shaped member is loosely mounted on said driven lever.

13. A self-locking control device according to claim 10 wherein said driven lever is provided therein with a substantially hemicylindrical recess and wherein said C- shaped member is provided with a substantially hemicylindrical portion disposed in and smaller than said recess, whereby said C-shaped member floats relative to said driven lever.

14. A self-locking control device as defined in claim 10 wherein said track member is an axially extending flange of an arcuate angle member having a radially extending flange secured to said supporting structure.

15.1n a self-locking control device of the character described, the combination of: a track member providing first and second surfaces on opposite sides thereof; a C- shaped member having spaced arms spanning said track member and receiving said track member therebetween, one arm of said C-shaped member providing a third surface facing and spaced from said second surface of said track member; at least one locking element between and engageable with said second and third surfaces; and a shoe carried by the other arm of said C-shaped member and slidably engaging said first surface of said track member.

16. In combination: a track extending between spaced points; a supporting member movable relative to said track between said points; locking means carried by said supporting member, and including movable locking elements engageable with said track, for locking said supporting member relative to said track in any position of said supporting member between said points; and lostmotion connecting means between said locking means and said supporting member and providing limited movement of said locking means relative to said supporting member in directions perpendicular to said track at each position of said supporting member between said points.

References Cited in the file of this patent UNlTED STATES PATENTS 2,171,458 Swartz Aug. 29, 1939 2,458,446 Suska Ian. 4, 1949 2,664,015 Moore Dec. 29, 1953 2,703,499 Reid Mar. 8, 1955 UNITED STATES PATENT ()FFICE CERTIFICATE OF CORRECTION Patent No, 2,855,800 I October 14., 1958 John M, Curtin It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 6, line 64, for "arms of which" read cw arms one of which n I SEAIJ ttest:

KARL HQAXLTNE ROBERT C. WATSON Attesting Oificer Commissioner of Patents 

